Should You Repair or Replace Your Asphalt?
Asphalt driveways and parking lots may last only 5 or 6 years before starting to breakdown if not maintained. Seal coating the asphalt surface is a good way to preserve it for an extended life. A life that may be as long as 25 or 30 years.
wide/fractured cracks - add asphalt overlay
That said, seal coating should never be applied to a fresh asphalt lay. At least 6 months must be given for the asphalt to completely cure. Those first months are critical to allowing volatile oils to evaporate from the asphalt. Waiting too long allows too much of those oils to escape.
narrow cracks - fill & seal
Sealing the asphalt every 3 years, traps those oils in the asphalt and slows down deterioration. As the oils leave the asphalt, the binders become more brittle and shrink. The brittleness allows the surface to break apart. The shrinkage allows water to penetrate, allowing ground swelling to speed up breakage.
Sealing asphalt can only go so far. Surfaces with depressions, gaps and large cracks cannot be filled with sealant. The only solutions are asphalt overlays or replacement.